Selection by compartmentalised screening

Abstract

The invention describes a method for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, by compartmentalizing the compounds into microcapsules together with the target, such that only a subset of the repertoire is represented in multiple copies in any one microcapsules; and identifying the compound which binds to or modulates the activity of the target. The invention enables the screening of large repertoires of molecules which can serve as leads for drug development.

1 - 108 . (canceled) 
     
     
         109 . A method for identifying a compound possessing a desired activity, the method comprising:
 providing a compound and target, each of which are in separate aqueous solutions;   compartmentalizing the compound into a first aqueous microcapsule that is surrounded by an immiscible fluid;   compartmentalizing the target into a second aqueous microcapsule that is surrounded by the immiscible fluid;   fusing the first and second microcapsules to form a fused microcapsule that is surrounded by the immiscible fluid, thereby causing a reaction between the compound and the target;   detecting the reaction in the fused microcapsule; and   identifying the compound that possess the desired activity.   
     
     
         110 . The method according to  claim 109 , wherein the compound is a nucleic acid. 
     
     
         111 . The method according to  claim 109 , wherein the compound is less than 500 Daltons. 
     
     
         112 . The compound according to  claim 109 , wherein the immiscible fluid is oil. 
     
     
         113 . The compound according to  claim 112 , wherein the oil is a fluorocarbon oil. 
     
     
         114 . The method according to  claim 109 , wherein the reaction is detected by detecting a change in optical properties of the fused microcapsule. 
     
     
         115 . The method according to  claim 114 , wherein the change in optical properties is a change in fluorescence. 
     
     
         116 . The method according to  claim 115 , wherein the change in fluorescence is due to fluorescence energy transfer (FRET). 
     
     
         117 . The method according to  claim 114 , wherein the change in optical properties is enhanced by said compound. 
     
     
         118 . The method according to  claim 114 , wherein the change in optical properties is inhibited by said compound. 
     
     
         119 . The method according to  claim 109 , wherein said desired activity induces a change in optical properties of the fused microcapsule. 
     
     
         120 . The method according to  claim 109 , wherein compartmentalizing the compound and the target occur under microfluidic control. 
     
     
         121 . The method according to  claim 120 , wherein the first and second microcapsules are flowing through at least one channel. 
     
     
         122 . The method according to  claim 120 , wherein the fusing step occurs in a channel. 
     
     
         123 . The method according to  claim 109 , further comprising sorting the compound after the identification. 
     
     
         124 . The method according to  claim 123 , wherein said sorting is conducted under microfluidic control. 
     
     
         125 . The method according to  claim 109 , wherein the first microcapsule comprises a single compound. 
     
     
         126 . The method according to  claim 109 , wherein the first microcapsule comprises multiple copies of a single compound. 
     
     
         127 . The method according to  claim 109 , wherein the target is selected from a cell, a G protein coupled receptor, a hormone receptor, a transcription factor, a cell wall component, and an enzyme. 
     
     
         128 . The method according to  claim 127 , wherein the enzyme is selected from a protein kinase, a protein phosphotase, and a replicase. 
     
     
         129 . The method according to  claim 109 , wherein the compound is attached to a microbead. 
     
     
         130 . The method according to  claim 129 , wherein the compound is attached to the microbead via a cleavable linker. 
     
     
         131 . A method for identifying a compound possessing a desired activity, the method comprising:
 providing a compound and target, each of which are in separate aqueous solutions;   compartmentalizing the compound into a first aqueous microcapsule that is surrounded by an immiscible fluid;   compartmentalizing the target into a second aqueous microcapsule that is surrounded by the immiscible fluid;   flowing the first and second microcapsules through a channel;   fusing the first and second microcapsules in the channel to form a fused microcapsule that is surrounded by the immiscible fluid, thereby causing a reaction between the compound and the target;   detecting the reaction in the fused microcapsule; and   identifying the compound that possess the desired activity.